diff --git a/layout/list.go b/layout/list.go
index cd32005d..97329f6c 100644
--- a/layout/list.go
+++ b/layout/list.go
@@ -5,6 +5,7 @@ package layout
 import (
 	"image"
 
+	"gioui.org/f32"
 	"gioui.org/gesture"
 	"gioui.org/io/pointer"
 	"gioui.org/op"
@@ -248,7 +249,7 @@ func (l *List) layout() Dimensions {
 		}
 		var stack op.StackOp
 		stack.Push(ops)
-		clip.Rect(r).Add(ops)
+		clip.Rect(ops, toRectF(r)).Add(ops)
 		op.TransformOp{}.Offset(toPointF(axisPoint(l.Axis, pos, cross))).Add(ops)
 		child.macro.Add(ops)
 		stack.Pop()
@@ -267,3 +268,10 @@ func (l *List) layout() Dimensions {
 	l.macro.Add(ops)
 	return Dimensions{Size: dims}
 }
+
+func toRectF(r image.Rectangle) f32.Rectangle {
+	return f32.Rectangle{
+		Min: f32.Point{X: float32(r.Min.X), Y: float32(r.Min.Y)},
+		Max: f32.Point{X: float32(r.Max.X), Y: float32(r.Max.Y)},
+	}
+}
diff --git a/op/clip/clip.go b/op/clip/clip.go
index 47a44470..68e28bb4 100644
--- a/op/clip/clip.go
+++ b/op/clip/clip.go
@@ -284,9 +284,17 @@ func (p *Path) End() Op {
 	}
 }
 
-// Rect returns the clip area of a pixel aligned rectangular area.
-func Rect(r image.Rectangle) Op {
-	return Op{bounds: toRectF(r)}
+// Rect returns the clip area of a rectangle.
+func Rect(ops *op.Ops, r f32.Rectangle) Op {
+	ri := image.Rectangle{
+		Min: image.Point{X: int(r.Min.X), Y: int(r.Min.Y)},
+		Max: image.Point{X: int(r.Max.X), Y: int(r.Max.Y)},
+	}
+	// Optimize pixel-aligned rectangles to just its bounds.
+	if r == toRectF(ri) {
+		return Op{bounds: r}
+	}
+	return RoundRect(ops, r, 0, 0, 0, 0)
 }
 
 // RoundRect returns the clip area of a rectangle with rounded
diff --git a/widget/material/image.go b/widget/material/image.go
index 318de388..6a4c2bef 100644
--- a/widget/material/image.go
+++ b/widget/material/image.go
@@ -37,7 +37,7 @@ func (im Image) Layout(gtx *layout.Context) {
 	d := image.Point{X: cs.Width.Constrain(w), Y: cs.Height.Constrain(h)}
 	var s op.StackOp
 	s.Push(gtx.Ops)
-	clip.Rect(image.Rectangle{Max: d}).Add(gtx.Ops)
+	clip.Rect(gtx.Ops, f32.Rectangle{Max: toPointF(d)}).Add(gtx.Ops)
 	im.Src.Add(gtx.Ops)
 	paint.PaintOp{Rect: f32.Rectangle{Max: f32.Point{X: float32(w), Y: float32(h)}}}.Add(gtx.Ops)
 	s.Pop()